Piranha A4 Replacement Blade 14 x 24 Used primarily on sterndrives (approximatey 112 Hp to 280 Hp) and outboard motors (approximatey 150 Hp+). These are semi-cupped propeller blades. These blades are used with A-4 style Piranha Propeller hubs. If you are not sure if this blade is appropriate for your use, please contact us for a recommendation.